Villagers in Chunquan Village, Wuxia Town, Wushan County, Chongqing see a doctor in the village health center. Xinhua news agency
Image source: Xinhua News Agency
Image source: Xinhua News Agency
Image source: Xinhua News Agency
Today, with the rapid development of science and technology, rumors under the banner of science are also emerging one after another. Moreover, many rumors like to start with the health and safety issues that the public cares about, sensationalize and create panic. A few days ago, under the guidance of the Beijing Association for Science and Technology, the Beijing Association of Editors of Science and Technology Journalists and the Beijing website jointly released the platform of dispelling rumors, "stop rumors and seek true knowledge — — Top Ten in 2019 ‘ Science ’ Most of the rumors in the gossip list are related to health. This edition extracts some health rumors and their truth interpretation and routine analysis to set the record straight.
Keywords: 5G base station radiation
● Gossip:
Mobile phone base stations have radiation, and 5G base stations are more than 4G, so 5G radiation will be greater than 4G, which is very harmful to human body.
● The truth:
Radiation is actually a way of energy transfer. Network speed-up has nothing to do with base station radiation increment. Network speed-up depends not on enhancing the signal transmission power of communication base stations, but on expanding transmission bandwidth, just like widening highways. The same is true for 5G communication base stations. Moreover, the more communication base stations there are, the better the effect of mobile phone calls, and the smaller the electromagnetic radiation generated between mobile phones and base stations.
The earth itself is a large magnetic field, and electromagnetic radiation is generated by lightning, thunder and sunspot activity in nature. In life, radio stations, base station antennas, microwave ovens, computers, televisions, hair dryers, radios and other household appliances that are inseparable from people’s lives will also produce electromagnetic radiation. Generally speaking, the radiation of the hair dryer can reach 100 microwatts/cm2, and the radiation of the induction cooker can even reach 580 microwatts/cm2. The wireless router commonly used in the home also generates more than 60 microwatts/cm2 within 1 meter.
The electromagnetic radiation of communication base stations should be less than 40 microwatts per square centimeter according to the requirements of national standards. In the actual implementation, the operator should consider the signal superposition, and the project construction should be controlled within 8 microwatts/cm2. Therefore, whether compared with national standards or common household appliances, the radiation of communication base stations is very small and will not cause harm to human body.
● Routine:
New things, exaggerated.
This kind of gossip takes advantage of people’s ignorance of new things and exaggerates them, so that rumors can be widely spread.
● Similar rumors:
1.PX is teratogenic, carcinogenic and highly toxic, and the explosion is comparable to an atomic bomb.
Truth: PX has a long history. It is a widely used low-toxicity chemical product and a raw material for medicine, perfume and ink.
2. Eating genetically modified food is childless, and Americans don’t eat it.
Truth: The safety evaluation of genetically modified food is much stricter than that of ordinary food, and the genetically modified food approved by the government is safe.
Keywords: high-speed rail radiation
● Gossip:
High-speed rail has had serious radiation problems since its birth, and the greatest harm to people is to destroy the female reproductive system and cause infertility.
● The truth:
Trains running on high-speed railways in China generally use 25,000 volts and 50 Hz alternating current. Accordingly, the high-voltage power equipment of high-speed rail radiates the electric field and magnetic field in this frequency band, which is "extremely low frequency electromagnetic radiation", belonging to non-ionizing radiation and will not affect women’s fertility. The statement that "high-speed rail radiation seriously causes infertility" is purely misleading.
Where there is electricity, there is radiation, ordinary trains and subways have radiation, mobile phones and razors have radiation, and sunlight also has radiation. As long as the radiation is within a safe value, it will not affect people. The International Commission on Non-ionizing Radiation Protection stipulates that the safety standard of magnetic field radiation generated by high-speed rail is below 100 micro Tesla (magnetic induction intensity unit), and the safety standard of electric field radiation is below 5 kV/m.
Professionals of Beijing Railway Department have specially measured the electric field radiation in high-speed rail cars and made the measured data public. The electric field radiation values of first-class cars, second-class cars, car joints, cabs and other positions of different models are distributed in the range of 0.011-0.021 kV/m.. Comparing these data, it is not difficult to find that the electromagnetic radiation of high-speed rail in China is far below international standards, and it is impossible to cause harm to human body.
● Routine:
Don’t talk about dosage, exaggerate the harm.
Alarming and exaggerating threats are the main characteristics of such rumors. Talking about radiation without dose has no practical significance in science. We have similar misunderstandings about many phenomena in life.
● Similar rumors:
1. Drinking coffee will cause cancer by ingesting acrylamide.
Truth: Acrylamide produced by high temperature in the process of making coffee is only potentially dangerous, and the content is very small. A person needs to drink at least 318 cups a day to have cancer risk.
2. The X-ray security instrument is harmful to human body.
Truth: The radiation of the security detector is far below the safety standard, so there is no need to worry about harm to the body.
Keywords: plague
● Gossip:
The mortality rate of plague is as high as 100%, and there is no cure. If you get infected, you will die!
● The truth:
Plague, also known as the Black Death, is a severe infectious disease caused by Yersinia pestis. According to different infection sites and clinical manifestations, plague can be divided into bubonic plague, pneumonic plague, septicemia plague, mild plague and other rare types of plague. Historically, plague did cause large-scale deaths, but it was because people didn’t know enough about the cause, treatment and prevention of plague at that time.
Although human beings are generally susceptible to plague, in modern medicine, plague is no longer hopeless. In fact, clinical plague cases can already be treated by standardizing the use of antibiotics. If patients can see a doctor early and get standardized treatment, the cure rate is very high, and suspicious contacts can also avoid getting sick by preventive medication.
However, it should be reminded that untreated plague patients have a very high mortality rate, such as the most dangerous pneumonic plague, which can be fatal within 18-24 hours of onset. If septic plague is not treated in time, the mortality rate is almost 100%. Therefore, early diagnosis and treatment are very important for patients to survive and reduce complications.
Gao Fu, academician of China Academy of Sciences and director of China CDC, said that at present, China has basically established a relatively complete prevention and control system. As long as it is scientifically responded, there will be no risk of widespread spread of plague.
● Routine:
In sensitive times, create panic.
Plague has caused heavy casualties in history, so related rumors spread rapidly when two cases of imported plague were found in Beijing. In the event of sudden events such as major epidemics and major disasters, people tend to be very sensitive and panic, and relevant rumors are easy to spread at this time. When dealing with extreme statements, we should develop the habit of questioning more.
● Similar rumors:
1. Sodium cyanide may cause toxic rain at the explosion site in Tianjin.
Truth: Solid sodium cyanide itself is highly toxic and can be dissolved in water, but it has no gaseous form in the conventional environment, so it is impossible to enter the air and spread with the wind, so there is no possibility of mixing with other components in the atmosphere and forming toxic rain by precipitation.
Smoking can prevent SARS.
Truth: It is recognized that smoking is harmful to health, one of which is to weaken the defense function of human respiratory system and increase the chance of infection. Besides, smoking also increases the contact between hands and nose and increases the chance of infection.
Eating iodized salt can prevent nuclear radiation.
Truth: The iodine content of iodized salt sold in the market is very low. In order to get the dose level required for the radiation protection of iodine, an adult needs to eat at least 2 to 3 kilograms at a time. Eating too much iodized salt or iodine tablets blindly according to the actual situation is harmful to the health and may cause diseases such as iodine exceeding the standard and iodine hyperthyroidism.
Keywords: thyroid nodules
● Gossip:
Detection of thyroid nodules is a precursor to thyroid cancer.
● The truth:
Generally speaking, most thyroid nodules are benign lesions, and real thyroid malignant tumors only account for a small part, so patients with thyroid nodules need not worry too much.
The diagnosis of thyroid cancer mainly depends on palpation, ultrasound, puncture and intraoperative pathology. With the continuous improvement of the resolution of modern ultrasound technology, more and more concealed papillary microcarcinoma of thyroid can be found, and most thyroid cancers can be cured through scientific and standardized treatment.
However, although there is no need to worry too much about thyroid nodules, we should not take them lightly. We need to go to a regular hospital as soon as possible for a definite diagnosis, so as not to delay the illness and miss the "golden time" of treatment.
In addition, because thyroid cancer usually has no obvious symptoms in the early stage, it is difficult to be detected. If there are symptoms such as sudden enlargement of nodules, dysphagia and adhesion of tissues near nodules, a comprehensive thyroid function test should be carried out to judge the nodules. Nodules that are difficult to distinguish should be examined regularly every 6 to 12 months.
● Routine:
Catering to demand, selling anxiety.
At present, people generally pay more attention to the topic of health and health preservation, but there are different opinions on online information, and some ambiguous rumors will take advantage of people’s psychological communication of "preferring to believe it, not believing it."
● Similar rumors:
1. There is rubbish in blood vessels, and if it is not cleaned up, it will be riddled with diseases.
Truth: There are no so-called garbage and toxins in blood vessels, but only metabolic wastes. Drinking plenty of water and increasing urination at ordinary times can help accelerate the cleaning of metabolic waste. In addition, any health food and detoxification soup can’t clear them out of the body.
2. Acidity is the root of all diseases.
Truth: The human body has an effective regulation system, which keeps the pH value basically stable and only fluctuates in a small range. In other words, eating any food will not change the pH value of the human body, and even drinking vinegar will not make the human body more acidic.
Keywords: artificial snow catalyst
● Gossip:
The large-scale snowfall in North China from February 13 to 14, 2019 was artificial snow increase. Silver iodide contained in artificial snow-increasing catalyst will endanger human health and cause environmental pollution.
● The truth:
In this snowfall, it is true that artificial snowfall has been carried out in some areas, but even if all the silver iodide catalysts used for snowfall have landed on the ground, the content of silver iodide per square kilometer is only 0.21g.. According to the precipitation, the silver ion concentration is about 0.000035 mg/L, which is far lower than the requirement of the World Health Organization standard and China’s national sanitary standard for drinking water that the silver content should not exceed 0.05 mg/L, and it will not pollute the ecological environment, and will not endanger human health.
As early as 1960s, scientific research institutions began to study the impact of silver iodide catalyst on the environment. The detection data of precipitation and soil after artificial rain and snow increase in the United States, Spain, Greece, Australia and Russia show that the average concentration of silver ions is very low. Therefore, the adverse impact of silver iodide, a catalyst used for weather modification, on the ecological environment can be ignored.
● Routine:
Technical terms lead to misinterpretation.
It is a common routine to take for granted the explanation of professional words that the public can’t understand, and spread it by taking advantage of people’s vanity that "I know more than you". Many people simply don’t know what "silver iodide" is, so they naturally believe and spread such rumors.
● Similar rumors:
1. Domestic salt contains potassium ferrocyanide, which is as toxic as arsenic.
Truth: Potassium cyanide is a well-known toxic substance, which is not the same as potassium ferrocyanide contained in salt. Potassium ferrocyanide is a low toxic substance, and a person needs to eat three or two salts a day to have a negative effect on the human body, while the salt that we normal people eat a day is already very salty when it reaches 20 grams.
2. Cereal contains pesticide glyphosate, which can cause cancer.
Truth: Scientific research shows that glyphosate has no negative effects on the development, reproduction and endocrine system of human beings and other mammals, and it has no chronic toxicity and neurotoxicity to animals in farmland within the scope of normal use.
Keywords: X-ray film
● Gossip:
X-ray has a great influence on human health, especially on pregnant women, babies and fetuses. Therefore, after taking the X-ray, I found that I was pregnant, so the child could not have it, and I had to have an abortion in time.
● The truth:
There is a threshold for the adverse effects of X-rays on all mammals, including humans, and even embryos. No matter for adults or fetuses, the radiation must reach a certain level to be damaged. Therefore, we can’t talk about the damage without the "dose" of radiation.
For the fetus, different gestational ages correspond to different safe doses of radiation. In 2017, the American Association of Obstetricians and Gynaecologists issued relevant guidelines: from 0 to 2 weeks of pregnancy, the threshold of teratogenic dose is 50 to 100mSv (millisieverts), and the main impact is fetal death; From 2 to 8 weeks of pregnancy, the threshold of teratogenic dose is 200mSv, and the main influence is congenital malformation; From 8 to 15 weeks of pregnancy, the threshold of teratogenic dose is 60 to 310mSv, which mainly affects mental development and deformity. Therefore, the threshold of the minimum influence dose of the fetus is 50mSv, which is safe as long as it does not exceed this value in theory.
In general, the radiation dose of an ordinary chest radiograph is 0.02mSv, that of a knee joint X-ray is 0.005mSv, that of a head CT is 2mSv, and that of a chest CT is 8mSv. Obviously, these radiation doses are within the safe range. To reach 50mSv is equivalent to 2,500 chest radiographs in continuous shooting, or 6 consecutive CT scans.
Many hospitals will take corresponding protective measures for those who are examined. For example, when taking a chest X-ray, the examinee will be put on a special lead hat and collar, and a heavy lead apron will be put around the waist and below to avoid unnecessary radiation to the human body.
● Routine:
Inertia thinking affects judgment.
In life, many medical institutions will remind pregnant women and pregnant people to avoid taking X-rays, which may make people form a "mindset", thus affecting rational analysis and judgment.
● Similar rumors:
1. The "grotesque" big strawberries are all hormonal.
Truth: hormones are substances that exist in plants themselves, and there is no need to talk about it. Most of the big strawberries on the market are "lucky" strawberries, which are very big in themselves. Some strawberries look strange, because the temperature and humidity conditions in the greenhouse are not good enough, and the lack of bees leads to uneven pollination.
2. Low outdoor visibility is caused by heavy pollution.
Truth: Atmospheric visibility is mainly affected by four factors: particle concentration, chemical composition, relative humidity and solar radiation. We often say that "air quality" only represents the concentration of particulate matter. In summer, the humidity of "sauna day" is relatively high, which significantly enhances the scattering effect of sunlight, resulting in a decrease in the amount of light input into people’s eyes, so the visibility is reduced.
Keywords: running
● Gossip:
People who run regularly are prone to hip and knee arthritis.
● The truth:
Risk factors leading to arthritis include age, family history, overweight and injury, but the length, intensity, distance and the number of long-distance runs completed have nothing to do with arthritis. In other words, people who are older, heavier, have a family history of arthritis or have had joint injuries are more likely to get arthritis.
Long-distance running does not destroy joints, but the proportion of marathon runners suffering from arthritis is lower than that of ordinary people. A large-scale study in 2017 showed that the incidence of arthritis in runners for fitness purposes was only 3.5%, while that in sedentary people was 10.2%. In other words, running can be a protective factor for the knee, and the key lies in the correct running mode.
In short, you should run within your power according to your physical condition. As long as the method is proper, it is beneficial to your joints and health.
● Routine:
Causality is confused and logic is misleading.
Misleading grafting causality. Succession or association is not equal to causality, and causality needs strict argumentation. It is a kind of thinking mistake that we often make to mistake the relationship of precedence or association for causality.
● Similar rumors:
1. Cold stimulation weakens the immune defense ability, and freezing can lead to arthritis.
Truth: By the age of 40, almost all people will have some pathological changes of osteoarthritis in their weight-bearing joints. Catch cold or catch cold is only an inducing factor that leads to the aggravation of arthritis symptoms, not a direct cause.
2. The woman in Xi ‘an died after being bitten by a dog and vaccinated, and the rabies vaccine was useless.
Truth: After the rabies vaccine is injected, there is indeed the possibility that the vaccine will be ineffective due to accidents, such as incomplete wound treatment and a small amount of virus remaining, but this does not mean that the vaccine is useless. In most cases, rabies vaccine is safe and effective.
